wp-includes/class-wp-customize-manager.php:6011Callback for validating the header_textcolor value.
$colorstringmixed public function _sanitize_header_textcolor( $color ) { if ( 'blank' === $color ) { return 'blank'; } $color = sanitize_hex_color_no_hash( $color ); if ( empty( $color ) ) { $color = get_theme_support( 'custom-header', 'default-text-color' ); } return $color; }Introduced in 3.4.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/class-wp-customize-manager.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.